The present invention relates to a controlling device and controlling method which perform control using a plurality of controllers within a predetermined energy consumption amount.
There has conventionally been known an apparatus (e.g., a semiconductor manufacturing apparatus using an electric heater as an actuator) which has a plurality of loops of a control system within one apparatus. This apparatus can prioritize and control the controllers of the respective control loops when the control characteristics of all the control loops are not so important. Controlling the controllers with priorities can suppress the power consumption amount (i.e., energy consumption amount). Assume that two control loops exist for a maximum heater output of 400 W. If these two controllers are controlled without any priority, the power equipment such as a power supply must provide 800 W; if these controllers are prioritized and controlled, the power equipment can be downsized.
Controllers are prioritized and controlled by a conventional method (to be referred to as the first prior art hereinafter) of sequentially operating them from a high-priority controller and operating lower-priority controllers within the remaining ability (feedable power amount). As another method, the abilities of controllers are lowered in accordance with a controller having the lowest operation speed (to be referred to as the second prior art hereinafter).
In the first prior art, a high-priority controller excessively takes precedence, and a low-priority controller hardly functions, failing to obtain the controllability of the low-priority controller. To operate even the low-priority controller, the ability of the overall apparatus must be increased, resulting in a large energy consumption amount and a bulky apparatus. In the first prior art, when controllers are set such that they operate within only fixed abilities designed in advance for the respective controllers on the basis of priority, the usable ability of the overall apparatus cannot be used up, leaving an unused ability.
In the second prior art, the ability of a high-priority controller is wasted. This means that a low-ability controller suffices to be used from the first, and sacrifices the controllability.